The purpose of thinking about the future is not to predict it but to raise people's hopes.

For me too, the periodic table was a passion. ... As a boy, I stood in front of the display for hours, thinking how wonderful it was that each of those metal foils and jars of gas had its own distinct personality.

Thanks to the discoveries of astronomers in the twentieth century, we now know that the heat death is a myth. The heat death can never happen, and there is no paradox.

The fundamental reason why carbon dioxide in the atmosphere is critically important to biology is that there is so little of it. A field of corn growing in full sunlight in the middle of the day uses up all the carbon dioxide within a meter of the ground in about five minutes. If the air were not constantly stirred by convection currents and winds, the corn would stop growing.

It is in the long run essential to the growth of any new and high civilization that small groups of men can escape from their neighbors and from their government, to go and live as they please in the wilderness. A truly isolated, small, and creative society will never again be possible on this planet.

If you go to London now, not everything is beautiful, but it's amazingly better than it was. And the Thames is certainly a lot better: There are fish in the Thames.

For some days I quietly worked out in my own mind the metaphysics of Cosmic Unity. The more I thought about it, the more convinced I became that it was the living truth. It was logically incontrovertible. It provided for the first time a firm foundation for ethics. It offered mankind the radical change of heart and mind that was our only hope of peace at a time of desperate danger. Only one small problem remained. I must find a way to convert the world to my way of thinking.